High temperature structural static seals are used in gas turbine engines and other equipment where high temperature fluids need to be sealed. These seals are traditionally made from cold formable or wrought superalloys. Conventional seals typically are made from superalloy sheet stock using a cold-forming procedure and can have different shaped cross sections. For example, some conventional cross-sections include the C (FIG. 1A), U (FIG. 1B) and E shapes (FIG. 1C), among other annular seals. These conventional annular seal rings are preferably installed between flanges, for example F1, F2 (FIG. 2), in a compressed condition.
The compression stress and the fluid pressure acting on these types of conventional annular seals provide sufficient sealing force to prevent the high pressure fluid from leaking through the interfaces where the seal and the flanges F1, F2 meet. At temperatures less than about 1300° F., as the flanges F1, F2 move back and forth, the elastic spring back of the seal cross-section maintains the sealing contact with the flange F1, F2, as best illustrated in FIG. 3.